Bug in v4 with `--inset-shadow-*` generating `inset` position rule

[Kinbaum]

What version of Tailwind CSS are you using?

v4.0.0-alpha.24

What build tool (or framework if it abstracts the build tool) are you using?

• next: 14.2.11
• tailwindcss: 4.0.0-alpha.24
• @tailwindcss/postcss: 4.0.0-alpha.24

What version of Node.js are you using?

v20.11.0

What browser are you using?

N/A

What operating system are you using?

macOS

Reproduction URL

https://play.tailwindcss.com/R5yKQBCPfX?file=css

Describe your issue

When using the --inset-shadow custom CSS property to generate an inset shadow, v4 is generating the inset position rule by mistake. Here is the generated output from the tailwindplay listed above (notice the highlighted section).

[adamwathan]

Oof good catch, this is going to be a fun one to fix 🙃 Thanks for reporting!

[Kinbaum]

Haha happy to help